Nonmedially assembled F-actin cables incorporate into the actomyosin ring in fission yeast
Nonmedially assembled F-actin cables incorporate into the actomyosin ring in fission yeast
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DOI：
10.1083/jcb.201209044
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发表时间：
2012-11-26
影响因子：
7.8
通讯作者：
Balasubramanian, Mohan K.
中科院分区：
文献类型：
--
作者：
Huang, Junqi;Huang, Yinyi;Balasubramanian, Mohan K.
在许多真核生物中，胞质分裂需要肌动球蛋白为基础的收缩环的组装和收缩。尽管这个环在胞质分裂中起着中心作用，但F-肌动蛋白在环中组装和积累的机制还不完全清楚。本文以LIFE为探针，研究了裂殖酵母胞质分裂过程中肌动蛋白F-肌动蛋白的组装机制。以往的工作表明，肌动球蛋白环中的F-肌动蛋白是在分裂位点重新组装的。令人惊讶的是，我们发现环中相当大一部分F-肌动蛋白是从Forin-Cdc12p有核的长肌动蛋白电缆中招募而来的，这些长肌动蛋白电缆在多个非中间位置产生，并通过肌球蛋白II和肌球蛋白V的结合进入环中。我们的结果以及在动物细胞中的发现表明，F-肌动蛋白在分裂部位的从头组装和在其他地方组装的F-肌动蛋白电缆的定向运输可能有助于环组装。
In many eukaryotes, cytokinesis requires the assembly and constriction of an actomyosin-based contractile ring. Despite the central role of this ring in cytokinesis, the mechanism of F-actin assembly and accumulation in the ring is not fully understood. In this paper, we investigate the mechanism of F-actin assembly during cytokinesis in Schizosaccharomyces pombe using lifeact as a probe to monitor actin dynamics. Previous work has shown that F-actin in the actomyosin ring is assembled de novo at the division site. Surprisingly, we find that a significant fraction of F-actin in the ring was recruited from formin-Cdc12p nucleated long actin cables that were generated at multiple nonmedial locations and incorporated into the ring by a combination of myosin II and myosin V activities. Our results, together with findings in animal cells, suggest that de novo F-actin assembly at the division site and directed transport of F-actin cables assembled elsewhere can contribute to ring assembly.